This invention relates to seat adjuster for a seat track assembly with a unique torque tube mounting configuration. Specifically, a plug member is rotatably supported on a seat track member and the torque tube engages the plug member to provided rotational input for vertical seat adjustment.
Seat adjusters are often used in seat assemblies for selectively adjusting the position of a vehicle seat. Seat adjusters have inboard and outboard track assemblies for horizontal seat adjustment. Typically each seat track assembly has a first track member is fixed to a vehicle structure, such as a floor, and a second track member is supported on the first track member for movement relative to the first track member such that the seat position can be adjusted forwardly or rearwardly with respect to the vehicle. The adjustment of the seat assembly is controlled by either a mechanical actuator, an electrical actuator, or an electro-mechanical actuator.
Typically, vertical seat adjustment is accomplished by torque tubes that actuate a drive link assembly that is connected to a seat bottom. An input is provided to the torque tubes which rotate to cause the drive links to move the seat bottom between a raised and lowered position. The torque tubes are installed such that they extend between the inboard and outboard track assemblies. Usually there is one torque tube installed between the track assemblies near the forward end for vertically adjusting the front portion of the seat and a second torque tube is installed between the track assemblies near the rearward end for vertically adjusting the rear portion of the seat.
The torque tubes are typically attached to the track assemblies with brackets and fasteners. This requires the seat adjusters to be shipped in a fully assembled condition. This takes up a significant amount of shipping space, which is undesirable. It would be desirable to have a simplified attachment for installing the torque tubes in the seat tracks such that the track assemblies and torque tubes could be shipped in an uninstalled configuration. The improved attachment should allow the torque tubes and the seat track assemblies to be quickly and easily connected on the assembly line.
In a disclosed embodiment, a seat mounting assembly includes a first track defining a longitudinal axis and a second track including a side wall having an opening. The first track is mounted to a vehicle structure and the second track is supported for linear movement relative to the first track along the longitudinal axis. A support member has a first portion that is partially received within the opening in the second track and is mounted for rotation with respect to the second track. At least one torque tube is supported by a second portion of the plug for rotation therewith to provide vertical seat adjustment.
In one embodiment, the support member includes a main body with an inner end and an outer end. The inner end has a first cross-sectional shape and presents a first external surface to define the first portion. The outer end has a second cross-sectional shape and presents a second external surface to define the second portion. In one preferred embodiment, the first cross-sectional shape is different than the second cross-sectional shape; specifically, the first cross-sectional shape is circular and the second cross-sectional shape is polygonal. The torque tube includes an elongated body with a central bore having a polygonal shape corresponding to the second cross-sectional shape. The outer end of the support member is received within the central bore to interconnect the support member and the torque tube.
Preferably, at least one adjustment link is mounted on the support member for rotation therewith to provide vertical seat adjustment to a seat bottom. The torque tube is connected to the support member and provides rotational input to the adjustment link. The adjustment link is mounted for rotation with the support member and is positioned between the second track and the torque tube.
A method of assembling the seat adjuster apparatus includes the following steps: providing a first track and a second track supported for movement relative to the first track and including a first bearing surface; inserting a support member into the second track such that the support member rotates relative to the second track; and mounting at least one adjustment link on the support member for rotation therewith. Additional steps include sliding a torque tube into engagement with the support member for providing rotational input to the adjustment link and deforming an end of the support member into engagement with the second track to prohibit axial movement relative thereto.
The subject invention provides a simplified torque tube mounting configuration for a seat adjuster that is durable, easily installed, and is inexpensive. Further, the improved mount reduces required packaging space for shipping the seat adjuster to the assembly plant. These and other features can be understood from the following specification and drawings.